Subscribe
Here is an interesting study that looked at the impact of urban highways on social connections within the 50 largest US cities. To measure this, the researchers used Twitter data from 2012-2013, which is a period of time where the default setting in the mobile app was to tag each tweet with the user's precise geographic coordinates.
This allowed the team to generally figure out where a user is likely to live. If you're often tweeting from the same residential address, then there's a good chance that's home. They then looked at things like mutual followship as a measure of social ties. And what they ultimately found was that in all 50 cities, urban highways exhibit a strong barrier effect. They measured this using something they call a "barrier score."
Now this sounds right and supports lots of other evidence that highways divide cities; but Twitter isn't necessarily a place where mutual followship means you actually know the person in real life and you regularly walk down the street to see if they can come out and play. So one of the things that the researchers also did was work to replicate their findings using data from another social network called Gowalla.
I very vaguely remember this platform, but it is/was a social network where users are supposed to connect with people they actually know and share their locations through check-ins. With this data they found that their "barrier score" was even more pronounced, which makes sense given that the platform's social graph should have had, in theory, stronger real-life ties.
But even if you don't believe the social data, these results should make intuitive sense. Highway underpasses and overpasses tend not to be the best environments for pedestrians. They're usually a clear break in a city's urban fabric, which can make people second guess whether they really want or need to cross it.
Cover photo by Tom Barrett on Unsplash
https://www.instagram.com/p/CREUPYgNCcQ/
American Forests, which is a US non-profit conservation organization, publishes something that they call a Tree Equity Score. What it effectively does is map tree cover across US cities. You can explore what that looks like, here. The score considers things like tree canopy, population density, income, race, as well as many other factors, and then produces a single score from 0 to 100. A score of 100 means that a neighborhood has achieved "Tree Equity."
There is seemingly a lot that you can glean from this score. For one, American Forests have found that income and race tend to correlate with tree canopy. Lower income neighborhoods tend to have less of it and rich neighborhoods tend to have more of it. You can start to see what that looks like in the Instagram post embedded at the top of this post. If it isn't showing up, click here.
But the other thing that is clear from these images is that rich people tend to consume more space. The richer tree-canopied neighborhoods appear to be less dense. The lots are bigger. And there are instances where the homes look to be adjacent to some large contiguous green spaces. This, of course, is a natural market outcome.
The Tree Equity Score tries to correct for this in its methodology. If a neighborhood's population density is very low (less than 2,000 people per km2), then it gets a higher tree canopy adjustment factor. It should have more trees. Conversely, if a neighborhood's population density is high (over 8,000 people per km2), then it's acceptable for there to be less trees (lower adjustment factor).
That said, it would be interesting to see a direct comparison of two neighborhoods -- one rich and one poor -- that have the exact same population densities and overall built form. I think that would speak volumes about tree inequity. I am also very curious about the global relationship between density and household incomes.
If any of you have a good source, please share it in the comment section below.
This morning I stumbled up on this conversation between Richard Florida and Ed Glaeser about the post-pandemic city. It's from September 2020 and that is obvious in some of the comments. Richard Florida (who was in Toronto) remarked that it felt like the pandemic was mostly over at that time and that Canada had seemingly done a much better job than the US at tackling it. That no longer feels right. But I did find myself agreeing with some of their other points.
Here's one from Ed Glaeser that looks back to previous health crises:
But pretty much since the 14th century, urbanization proceeded despite the reappearance of the Black Death in the 1350s. Urbanization proceeded despite the Great Plague of London in the 1660s. All of the great diseases that spread in 19th-century America, cholera, yellow fever, the urbanization just chugged along. Even the influenza pandemic of 1919-1920 was followed by a tremendous decade of city building. So, I think our cities have proven to be remarkably resilient.
For the full conversation, click here.
Here is an interesting study that looked at the impact of urban highways on social connections within the 50 largest US cities. To measure this, the researchers used Twitter data from 2012-2013, which is a period of time where the default setting in the mobile app was to tag each tweet with the user's precise geographic coordinates.
This allowed the team to generally figure out where a user is likely to live. If you're often tweeting from the same residential address, then there's a good chance that's home. They then looked at things like mutual followship as a measure of social ties. And what they ultimately found was that in all 50 cities, urban highways exhibit a strong barrier effect. They measured this using something they call a "barrier score."
Now this sounds right and supports lots of other evidence that highways divide cities; but Twitter isn't necessarily a place where mutual followship means you actually know the person in real life and you regularly walk down the street to see if they can come out and play. So one of the things that the researchers also did was work to replicate their findings using data from another social network called Gowalla.
I very vaguely remember this platform, but it is/was a social network where users are supposed to connect with people they actually know and share their locations through check-ins. With this data they found that their "barrier score" was even more pronounced, which makes sense given that the platform's social graph should have had, in theory, stronger real-life ties.
But even if you don't believe the social data, these results should make intuitive sense. Highway underpasses and overpasses tend not to be the best environments for pedestrians. They're usually a clear break in a city's urban fabric, which can make people second guess whether they really want or need to cross it.
Cover photo by Tom Barrett on Unsplash
https://www.instagram.com/p/CREUPYgNCcQ/
American Forests, which is a US non-profit conservation organization, publishes something that they call a Tree Equity Score. What it effectively does is map tree cover across US cities. You can explore what that looks like, here. The score considers things like tree canopy, population density, income, race, as well as many other factors, and then produces a single score from 0 to 100. A score of 100 means that a neighborhood has achieved "Tree Equity."
There is seemingly a lot that you can glean from this score. For one, American Forests have found that income and race tend to correlate with tree canopy. Lower income neighborhoods tend to have less of it and rich neighborhoods tend to have more of it. You can start to see what that looks like in the Instagram post embedded at the top of this post. If it isn't showing up, click here.
But the other thing that is clear from these images is that rich people tend to consume more space. The richer tree-canopied neighborhoods appear to be less dense. The lots are bigger. And there are instances where the homes look to be adjacent to some large contiguous green spaces. This, of course, is a natural market outcome.
The Tree Equity Score tries to correct for this in its methodology. If a neighborhood's population density is very low (less than 2,000 people per km2), then it gets a higher tree canopy adjustment factor. It should have more trees. Conversely, if a neighborhood's population density is high (over 8,000 people per km2), then it's acceptable for there to be less trees (lower adjustment factor).
That said, it would be interesting to see a direct comparison of two neighborhoods -- one rich and one poor -- that have the exact same population densities and overall built form. I think that would speak volumes about tree inequity. I am also very curious about the global relationship between density and household incomes.
If any of you have a good source, please share it in the comment section below.
This morning I stumbled up on this conversation between Richard Florida and Ed Glaeser about the post-pandemic city. It's from September 2020 and that is obvious in some of the comments. Richard Florida (who was in Toronto) remarked that it felt like the pandemic was mostly over at that time and that Canada had seemingly done a much better job than the US at tackling it. That no longer feels right. But I did find myself agreeing with some of their other points.
Here's one from Ed Glaeser that looks back to previous health crises:
But pretty much since the 14th century, urbanization proceeded despite the reappearance of the Black Death in the 1350s. Urbanization proceeded despite the Great Plague of London in the 1660s. All of the great diseases that spread in 19th-century America, cholera, yellow fever, the urbanization just chugged along. Even the influenza pandemic of 1919-1920 was followed by a tremendous decade of city building. So, I think our cities have proven to be remarkably resilient.
For the full conversation, click here.
Share Dialog
Share Dialog
Share Dialog
Share Dialog
Share Dialog
Share Dialog
